Auger



llirnn ra'rne ATENT HENRY G. \YATROUS, OF \VALLINGFORD, CONNECTICUT.

Adena.

SPECIFICATION forming part of LettersPatent Ito. 606,319, dated June 28, 1893. 1

Application filed N v m r 16, 1897.' $erial No. 658,676. (No model.) i i To (LZZ whom it may concern.-

Be it known that I, HENRY Gr. \VATROUS, of \Vallingford, in New Haven county, C011- necticut, have invented certain new and usef ul Improvements in Angers, which improve ments are described in the following specification and are illustrated by the accompanying drawings.

My invention relates to that class of angers commonly called double twist angers, which are formed from a; iiat plate twisted, and are provided with terminal cutting devices to facilitate the entrance of the tool into wood or other material in boring.

In general terms it is the primary object of my invention to obtain in angers of the de scribed class the general mode of operation belonging to that other class of angers commonly called ship-angers, which are form ed on the plan of a single spiral twist or coiled bar.

As the making of a double-twist anger is much less expensive than the making of a single-twist auger, it is a particular object of the invention to render a double-twist auger a good and efiicient substitute for a singletwist anger in the interest of cheapness of manufacture, and as a double-twist anger is stiffer and stronger than a single-twist anger of the same size and weight it is a further particular object of the invention to diminish the weight of boring-tools that have the specified general mode of operation.

It is a yet further particular object of the invention to secure uniformity of action of my improved auger by definitely predeterlnining in a special manner the maximum thickness of the chip that is to be cut by the tool in boring.

To accomplish these objects, I adopt in the construction of the auger a pod or barrel that is formed 011 the plan of a fiat ribbon twisted, and provide that pod not with two cutters or routers after the usual nianner of doubletwisted angers, but with a single cutter, after the manner of single-twist angers, and also with a heel which has a peculiar form and a special mode of operation.

The best mode in which I have contemplated applying the principles of the invention is shown in the said drawings, by which the invention is illustrated.

In the drawings, Figures 1 and 2 are oppo-' site side views of a portion of an anger that is constructed in accordance with those principles, while Fig. 3 is a side View of the same turned through an angle of ninety degrees. Fig. 4 is afront end view of the same. Fig. 5 is a front end view of my improved auger when made without a screw-point.

In the views the numerals land 2 denote two spiral ribs parallel and diametrically opposite to each other which wind around the aXis of the auger and correspond, respectively, to the opposite edge portions of the flat plate or blank from which the implement has been formed by twisting. Between them are two similar and separate spiral grooves 3 and 4, winding about the same axis from end to end of the pod in the usual manner.

The numeral 5 denotes a screw-point in ad- Vance of the spiral ribs and upon the same axis. The forward end of rib 1 is armed with a sharp side lip 0, after the manner of shipaugers, and with a router '7, whose cutting edge is continuous with a thread of the screwpoint 5. \Vhen the implement is made with out any screw-point, as many ship-augers are, the cutting edge of the router 7 is made longer and extends by the aXis aforesaid, as shown in Fig. 5. The forward end of rib 2, instead of being also armed with a cutter, ends bluntly with a heel S, opposite the router 7. The anterior surface of this heel being beveled in two directions has two adjacent faces 9 and 10, which are inclined to each other at an obtuse angle. They lie on opposite sides of that part of the heel which is most advanced along the said axis of the tool and whichis indicated in Fig. i by the broken line 11. The mutual inclination of the faces 9 and 10 neoessarily varies with the pitch of the spiral ribs. In every instance it is made such as to allow the heel to circle around without impediment on the sloping bottom of the hole that is being bored.

The remaining particulars of construction of my improved auger will be apparent from its mode of operation, which now remains to be described.

eration of the described boring-tool is that of angers formed on the plan of a coiled bar. Like them it will bore when made without a As above proposed, the general mode of op:

screw-point; like them it regularly discharges.

ICO

the thread upon the screw-point.

the chip through a single channel-namely, the groove 3; like them it works with the diminished friction thatis due to the use ofa single cutter in place of the two cutters that are commonly used in other double-twist angers, and like them it definitely predetermines the thickness of the chip that may be cut independently of the attention of the workman, the inclination of the router, and the pitch of Unlike them it works with the diminished friction that is due to the use of two thin spiral ribs with a vacant space between them instead of a broad-backed coiled bar in contact with the sides of the auger-hole; unlike them it works with the further diminished friction that is due to using a beveled heelseparated from the router instead of a single cutter and heel continuously in contact with the bottom of the augerhole; unlike them it is cheap and easy to manufacture and is especially adapted by the disposition of its material to resist the torsional strains of service, and unlike them it has the superior clearance that is due to the use of two discharging-channels separated only by a narrow rib. A broken chip escaping from groove 3 may be carried out by groove 4 instead of clogging behind the back of a thick coiled bar. As compared with augers that have in the head only a single spiral groove, my invention has the advantage of being lighter without being effectually weaker. As compared with double twist angers of earlier construction, it presents all the advantages of the described general mode of operation of single-twist angers, including the automatic limitation of the thickness of the chip and the consequent regularity in the action of the tool. In my improved anger those results are obtained by the novel method of forming upon the blunt end of the spiral rib 2 the doubly-beveled heel 8, which slides rotarily down the sloping floor of the auger-hole as it deepens in boring.

Such being the construction and operation of my invention, I claim- In a boring-tool,the combination of two parallel ribs, coiling around a common axis, and terminally provided, one with a router and side lip, and the other with a heel, which has two contiguous inclined faces, situated at a predetermined distance behind the path of the router, substantially as and for the purpose specified.

In testimony whereof I hereunto set my name in the presence of two witnesses.

HENRY G. XVATROUS.

\Vitnesses:

WILLARD EDDY, WILLIAM B. MOELNEY. 

